Sen. David Perdue, of Georgia, also defended Trump's refusal to comply with subpoenas issued to his administration by House Democrats and said they need to decide if they are going to "legislate or investigate."

Perdue, who was in the Capitol briefly to oversee a pro forma session, said he had read the Mueller report.

"First of all, there was no collusion. There was no evidence of obstruction that they could do anything with," he told reporters as he left the floor. "It's time to move on. It's time to move on."

The points by Purdue -- who is running for reelection this cycle in what could be a competitive race -- are likely to be echoed by other congressional Republicans when they return Monday from a two-week recess that had them out of Washington when a redacted version of Mueller's report was released to the public.

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Sen. Mitt Romney, a Utah Republican, blasted Trump's actions that are outlined in the report. But most other Republicans have said little about the specific allegations of obstruction or cooperation with the Russians during the 2016 campaign, even as Democrats who control the House ratchet up their post-Mueller investigations. Those efforts include issuing multiple subpoenas that Trump is saying his administration will fight.

Asked about Trump's refusing to allow his aides to comply with subpoenas, Perdue said, "He's not the first president to have done that."

He added, "Frankly, I think it's absurd. The House needs to decide, are they going to legislate or investigate, and right now they're saying they're going to investigate. The rest of the world out here is going to remember that."

Perdue also said the administration may comply with some subpoenas.

"They haven't made any general statements about any decision about all subpoena, they are reacting to each one individually," he said.

Perdue did say he believed there is some room for investigative oversight of the Trump administration.

"Well, of course. They've been doing it for two years. That's what this whole thing has been about. He supported it. He did it. He created the special investigator. I don't think that's a fair question," Perdue said.